Alkyl Chain Regulated Aggregated State Luminescence in TICT-Type AIEgens.

Aggregation-induced emission luminogens (AIEgens) effectively overcome the aggregation-caused quenching (ACQ) limitations of traditional luminogens, enabling broad applications in sensing, bioimaging, radiation detection, and photovoltaic conversion. Among them, twisted intramolecular charge transfer (TICT)-type AIEgens, featuring rotatable donor-acceptor (D-A) structures, exhibit pronounced polarity-dependent luminescence, making them promising candidates for environmental and multi-stimuli-responsive functional materials. To further regulate their TICT behavior in the aggregated state, alkyl chains of different lengths were introduced into the AIEgens design. Along with the increase of alkyl chain from 4 carbons to 16 carbons, the emission wavelength of the TICT-type AIEgens redshifted significantly along with a decrease of emission intensity. This work provides a brand-new strategy to facilely regulate the luminescence properties of TICT-type AIEgens in the aggregated state.